Endodontic failure and implant rehabilitation: the challenge of alveolar preservation

The failure of endodontic treatment, often linked to persistent bacterial infection, presents the practitioner with a clinical dilemma: attempting complex retreatment or opting for a long-term implant solution. In this case report, a 46-year-old patient presents with persistent periapical pathology on the left maxillary first molar, making the prognosis for conservation unfavorable. The major challenge then lies in managing the physiological bone resorption following extraction, which is likely to compromise future implant positioning.

The objective of this presentation is to document, through a rigorous radiographic sequence, the success of a staged implant rehabilitation. The study illustrates how an alveolar preservation procedure, via a bone graft performed immediately after avulsion, maintains the ridge dimensions necessary for delayed implantation. The authors validate here the reliability of a systematic protocol including a three-month healing phase before implant placement, followed by a prosthetic restoration via digital workflow. This approach aims to demonstrate that rigorous management of the extraction site is the key to predictable functional integration and long-term restorative success.

Case report methodology

This case report documents the sequential implant rehabilitation of a 46-year-old male patient (ASA I) presenting with endodontic treatment failure on the left maxillary first molar (#14). Clinical management is based on an alveolar preservation approach aimed at limiting post-extraction bone resorption.

The surgical protocol followed a precise therapeutic schedule:

• Initial phase: Preoperative prescription of amoxicillin (500 mg) for seven days.
• Extraction and grafting: Atraumatic exodontia of tooth #14 immediately followed by a ridge preservation procedure using bone grafting under membrane.
• Healing cycle: A three-month period was observed to allow for bone maturation before the surgical placement of the implant into the grafted site. A second three-month period was respected to ensure osseointegration.
• Prosthetic rehabilitation: Acquisition of a digital impression via a scan body for the prosthesis design, followed by the placement of the final implant-supported crown three weeks later.

The evaluation of outcomes was based on rigorous clinical and radiographic follow-up. Serial periapical radiographs were performed to document the evolution at each critical stage: diagnosis of endodontic failure, verification of alveolar grafting, implant positioning, digital impression transfer, and final placement of the restoration.

Clinical follow-up and radiographic progression

The success of the rehabilitation was documented by a series of periapical radiographs, confirming tissue integration at each stage of the sequential protocol. Initially, imaging revealed persistent periapical radiolucency at the apices of tooth #14, confirming the failure of the endodontic treatment and justifying the extraction.

After the atraumatic extraction, the socket preservation procedure was immediately implemented. The post-operative radiograph validated the placement of the bone graft material, visualised as a radio-opaque mass filling the socket. This step allowed for the stabilisation of the alveolar ridge dimensions during the healing phase.

The surgical phase was followed by a three-month healing period to promote bone maturation. Following this period, a dental implant was positioned in the healed site. A second three-month period was observed to ensure osseointegration before loading.

Sur le plan prothétique, l'utilisation d'un scan body a permis le transfert numérique précis de la position implantaire. La restauration définitive a été livrée trois semaines après l'empreinte optique. Le cliché final confirme une adaptation prothétique optimale et une réhabilitation fonctionnelle complète du site édenté, sans signe de pathologie péri-implantaire.

Analysis of sequential rehabilitation

This clinical case illustrates the rigor required to transform an endodontic failure on a maxillary first molar into a lasting implant success. The staged strategy, separating alveolar preservation from implant placement, allowed for optimal stability despite the initial periapical pathology. Clinically, this confirms that respecting bone maturation times — approximately three months after grafting — remains a predictability standard to secure osseointegration.

The integration of the digital workflow through the use of a scan body for the final impression highlights the contribution of current technologies to the practice. This method increases the reliability of the implant position transfer to the laboratory, ensuring precise prosthetic adaptation during the crown placement. However, this case report presents inherent limitations due to its design: the clinical follow-up ends at the placement of the final prosthesis and no three-dimensional radiographic analysis (CBCT) was used to precisely quantify the volumetric maintenance of the alveolar ridge.

The documented approach here emphasizes that managing an infected site requires thorough debridement during extraction before any preservation procedure. By following this systematic protocol, the practitioner ensures sufficient bone volume for ideal implant positioning, thus avoiding more invasive reconstructive surgeries.

Case report summary

This clinical case in a 46-year-old patient demonstrates the efficacy of a sequenced protocol following endodontic failure on tooth 14. Immediate alveolar preservation allowed for implant placement after 3 months of bone healing, followed by a 3-month osseointegration phase and a final prosthetic restoration via digital workflow delivered in 3 weeks.

In concrete terms, for the practitioner:

• Secure bone volume: Systematize alveolar preservation during the extraction of a maxillary molar to counter physiological remodeling and ensure optimal implant positioning.
• Respect biological chronology: Prioritize a staged approach (3 months post-graft, then 3 months post-implantation) to ensure predictable bone maturation and osseointegration.
• Optimize prosthetic precision: Use scan bodies and digital workflow to ensure reliable implant position transfer, facilitating rapid delivery of the final crown.

Technical lexicon of the study

Socket preservation (Alveolar preservation): Bone grafting procedure performed immediately after extraction to minimize physiological ridge resorption and maintain adequate bone volume for subsequent implantation.

Scan body: Position transfer device connected to the implant to accurately transmit spatial data to the prosthetic laboratory, allowing for design via a digital workflow.

Periapical radiolucency: Radiographic image of decreased density located at the root apices, characteristic in this case of persistent apical pathology and endodontic treatment failure.

Osseointegration: Biological healing process resulting in the functional stability of the implant in the alveolar bone, promoted here by a three-month resting period after placement.

Xenogeneic bone graft: Bone substitute material used for the regeneration and maintenance of alveolar ridge dimensions prior to implant rehabilitation.

Digital workflow: Rehabilitation protocol integrating digital impression acquisition and computerized data transfer for the manufacture of the definitive crown.

Information intended for healthcare professionals. This content may contain errors or truncated summaries. We recommend always verifying with the original source article. Delynov disclaims all responsibility for the use of this information. This document is not intended for patients or the general public.